Bài 1:
a) ( x + 1 )( x - 3 ) ≤ 0
b) \(\left(x^2+1\right)\left(x-2\right)\) ≥ 0
Bài 2:
a) \(\frac{x-2}{x+1}< 0\)
b) \(\frac{-2}{x-1}>0\)
c) \(\frac{x-1}{x+3}>0\)
d)\(\frac{x^2-x+1}{x+3}>0\)
e) \(\frac{x-2}{x+1}\) ≤ 0
f) \(\frac{x^2}{x-3}\) ≥ 0